Earnest Gary Gygax (July 27, 1938 – March 4, 2008)
In the 1960s, Gygax created an organization of wargaming clubs and founded the Gen Con tabletop game convention. In 1971, he co-developed Chainmail, a miniatures wargame based on medieval warfare with Jeff Perren. He co-founded the company TSR (originally Tactical Studies Rules) with childhood friend Don Kaye in 1973. The next year, TSR published D&D, created by Gygax and Arneson the year before. In 1976, he founded The Dragon, a magazine based around the new game. In 1977, he began developing a more comprehensive version of the game called Advanced Dungeons & Dragons. He designed numerous manuals for the game system, as well as several pre-packaged adventures called "modules" that gave a person running a D&D game (the "Dungeon Master") a rough script and ideas. In 1983, he worked to license the D&D product line into the successful D&D cartoon series.
Donald R. Kaye (born June 27, 1938)
Kayne was the co-founder of TSR, Inc., and was the childhood friend of Gary Gygax, and shared an interest in war games and tabletop miniatures with him during their youth. When Gygax was co-developing the game that would become known as Dungeons & Dragons (D&D) in 1972, Kaye played in the second-ever session; his character, Murlynd, was one of the first D&D characters created as well as one of the earliest explorers of the dungeons under Gygax's Castle Greyhawk. Kaye and Gygax became convinced that D&D and similar games were an excellent business opportunity, and together they founded TSR, Inc. in 1973. However, only two years later, just as sales of D&D started to increase exponentially, Kaye unexpectedly died of a heart attack at age 36. With no provision made for a partner's death, the stage was set for Gygax to lose control of TSR and ultimately be forced out of the company a decade later.
David Lance Arneson (October 1, 1947 – April 7, 2009)
Arneson discovered wargaming as a teenager in the 1960s, and he began combining these games with the concept of role-playing. He was a University of Minnesota student when he met Gygax at the Gen Con gaming convention in the late 1960s. In 1971, Arneson created the game and fictional world that became Blackmoor, writing his own rules and basing the setting on medieval fantasy elements. Arneson took the game to Gygax as the representative for game publisher Guidon Games, and the pair co-developed a set of rules that became Dungeons & Dragons (D&D). Gygax and Donald Kaye subsequently founded Tactical Studies Rules in 1973, which published Dungeons & Dragons the next year